Preheat oven to 425 degrees. Grease muffin cups or line with paper muffin liners. In a small bowl, combine milk and oats; let soak for 15 minutes. In a separate bowl, beat together egg and oil; stir in oatmeal mixture. In a third bowl, sift together flour, sugar, baking powder and salt. Stir flour mixture into wet ingredients, just until combined. Spoon batter into prepared muffin cups until cups are 2/3 full. Bake for 20 to 25 minutes, or until muffins test “done” with a toothpick.